Previous studies have demonstrated that income has a significant effect on food demand in rural China. However, little research has focused on the dynamic impact of income and income distribution on food demand in rur...Previous studies have demonstrated that income has a significant effect on food demand in rural China. However, little research has focused on the dynamic impact of income and income distribution on food demand in rural China. Using China Health and Nutrition Survey data, this study employs a consistent two-step quadratic almost ideal demand system model, with addressed problems of endogeneity of total expenditure and zero shares, to estimate the food demand elasticities among adults in rural areas with regard to the different income strata. The results show that changes in income and income strata have significant effects on food demand in rural areas. Except for grains, all other food groups, including vegetables, oils and fats, animal products, and other foods, have positive income elasticities, and the rise in the income strata will lead to declining income elasticities for grains, vegetables, oils and fats, and animal products. Based on the estimated income elasticities, the food consumption projections indicate that reducing income inequality in rural society can improve the living standard of low-income people in terms of nutrient intakes.展开更多
The development of a multi-pillar pension insurance system is an effective solution for an aging society.Commercial pension insurance,as the third pillar of pension insurance,is an integral part of this system in Chin...The development of a multi-pillar pension insurance system is an effective solution for an aging society.Commercial pension insurance,as the third pillar of pension insurance,is an integral part of this system in China and can play a critical and complementary role in rural areas where support for the elderly is a more pressing concern and a second pillar of pension insurance remains absent.To this end,we first elaborate on the theoretical logic that commercial pension insurance can develop into one of the pillars of rural pension insurance.We then empirically test rural residents’willingness to participate in a commercial pension insurance plan(CPIP)in a probit model with household research data from rural areas in major labor-exporting provinces,such as Sichuan and Henan so as to explore whether commercial pension insurance has the potential to become one of the pillars of rural pension insurance.Our research findings can be synthesized in three points.First,rural residents out of agricultural production for five consecutive years are more willing to participate in a CPIP than other rural residents,indicating that progress in industrialization and urbanization can significantly boost such willingness.Second,the younger rural residents are more inclined to participate in a CPIP than the older generation.Third,income increases can significantly boost rural residents’willingness to participate in a CPIP.Thus,with progress in industrialization and urbanization and an increase in rural disposable income,commercial pension insurance has a promising potential in rural areas and can hopefully develop into one of the pillars of rural pension insurance.展开更多
In China, farmers employed in non-farm work have become important socio-economic actors, but few studies have examined the farmers' perspective in making their work location choices. Based on "push-pull"...In China, farmers employed in non-farm work have become important socio-economic actors, but few studies have examined the farmers' perspective in making their work location choices. Based on "push-pull" migration theory, this paper utilizes sectional data from a 2013 survey of farmers in China's Three Gorges Reservoir area to empirically analyze the factors influencing migrant workers' choice of employment location. The results indicate that 60.46% of laborers have migrated from their home province, whereas 39.54% have remained in their home province. Focusing on personal, household, and community characteristics—in addition to the economic characteristics of the sample counties—multinomial logistic regression models reveal that farmer-laborers' employment location decisions are influenced by their personal capital endowment(age, years of education and social networks), family structure(the number of laborers, elders, children and students), home village characteristics(location, economic development level and the degree of relief of the land) and home county economic development level. Notably, male and female laborers' location decisions reveal a converging trend, and their differences are not pronounced. Per capita arable land area has little influence on location decisions, whereas the educational level of laborers has a significant impact. The results differ significantly from those found in previous studies.展开更多
Based on panel data from the Rural Fixed Point Survey of the Ministry of Agriculture over the period 2004-2016 and supplementary survey data on information and communications technology(ICT)applications in the country...Based on panel data from the Rural Fixed Point Survey of the Ministry of Agriculture over the period 2004-2016 and supplementary survey data on information and communications technology(ICT)applications in the countryside,this paper employs the difference in differences(DID)method to analyze the effects of ICT applications on rural households’agricultural total factor productivity(TFP)with mobile phone signal,internet and 3G mobile network connections as indicators,and decomposes and evaluates the constituent factors.Our findings reveal a positive effect of ICTs on rural households’TFP,which primarily stemmed from rising agricultural technical efficiency.However,ICTs exerted no significant effect on agricultural technical progress during this paper’s data period due to limited rural human capital.These findings are consistent with robustness test results based on counterfactual and matching methods.展开更多
Climate extreme events have threatened food security and the second Sustainable development goals (SDGs) “zero hunger” both directly via agricultural food loss and indirectly through rising food prices. We systemati...Climate extreme events have threatened food security and the second Sustainable development goals (SDGs) “zero hunger” both directly via agricultural food loss and indirectly through rising food prices. We systematically searched and used a combination of results from various models, which play a crucial role in predicting the potential impact of climate change on agricultural production and food price. Therefore, we searched online databases including EMBASE, Web of Science, Scopus, Google Scholar, and grey literature. Then observational studies were included from January 1990 to August 2021, which reported food price proportion under climate disturbances. Results showed that 22 out of 26 studies from 615 articles, identified in the meta-analysis predicted the food price ratio would be fluctuated up to 28% before 2020, while the ratio will be marked up at 31% from 2020 to 2049 and then will scale down during 2050-2100. The compiled ratio was estimated at 26% in the long period between 2000 until 2100 under climatic weather events. Drought was a significant weather disturbance with a 32% increase in food prices. Consequently, the Food price increase will significantly affect food accessibility in lower-income countries, primarily until 2050. Policymakers should prioritize and act through redesigning food security policies according to climatic extremes in their settings.展开更多
Segmentation of vegetation remote sensing images can minimize the interference of background,thus achieving efficient monitoring and analysis for vegetation information.The segmentation of vegetation poses a significa...Segmentation of vegetation remote sensing images can minimize the interference of background,thus achieving efficient monitoring and analysis for vegetation information.The segmentation of vegetation poses a significant challenge due to the inherently complex environmental conditions.Currently,there is a growing trend of using spectral sensing combined with deep learning for field vegetation segmentation to cope with complex environ-ments.However,two major constraints remain:the high cost of equipment required for field spectral data collection;the availability of field datasets is limited and data annotation is time-consuming and labor-intensive.To address these challenges,we propose a weakly supervised approach for field vegetation segmentation by using spectral reconstruction(SR)techniques as the foundation and drawing on the theory of vegetation index(Ⅵ).Specifically,to reduce the cost of data acquisition,we propose SRCNet and SRANet based on convolution and attention structure to reconstruct multispectral images of fields,respectively.Then,borrowing from theⅥprinciple,we aggregate the reconstructed data to establish the connection of spectral bands,obtaining more salient vegetation information.Finally,we employ the adaptation strategy to segment the fused feature map using a weakly supervised method,which does not require manual labeling to obtain a field vegetation segmentation result.Our segmentation method can achieve a Mean Intersection over Union(MIoU)of 0.853 on real field datasets,which outperforms the existing methods.In addition,we have open-sourced a dataset of unmanned aerial vehicle(UAV)RGB-multispectral images,comprising 2358 pairs of samples,to improve the richness of remote sensing agricultural data.The code and data are available at egment_SR,and.展开更多
This study aimed to determine the sustainability criteria of the beekeeping industry in Iran,which was performed using three-stage classical Delphi technique.The participants were 32 experts in beekeeping industry who...This study aimed to determine the sustainability criteria of the beekeeping industry in Iran,which was performed using three-stage classical Delphi technique.The participants were 32 experts in beekeeping industry who were purposefully selected using the snowball sampling method.The criteria identified,after three Delphi stages,consisted of 70 items,which were categorized into 13 general criteria and into four economic,environmental,social,and institutional dimensions.The general criteria were presented in the form of a conceptual model,including:farmers’environmental behavior quality,beekeepers'environmental behavior quality,the quality of marketing and sales of beekeeping productions,productivity and performance improvement,amount of monetization from pollinations'right,the amount of monetization of byproducts and value added,employment rate and job stability,the level of social development of stakeholders,the quality of the role-playing of non-governmental stakeholders,the quality of extension and education new sciences and technologies to stakeholders,comprehensiveness of laws and programs,quality of role-playing of stakeholder non-governmental organizations,and the quality of the roleplaying of governmental institutions stakeholder.Using them,a comprehensive perception of the necessary criteria for the sustainability of Iran's beekeeping industry can be obtained and a comprehensive program can be designed for its implementation.展开更多
We synthesized LiMnPO4/C with an ordered olivine structure by using a microwave-assisted polyol process in 2：15 （v/v） water-diethylene glycol mixed solvents at 130℃ for 30min. We also studied how three surfactants...We synthesized LiMnPO4/C with an ordered olivine structure by using a microwave-assisted polyol process in 2：15 （v/v） water-diethylene glycol mixed solvents at 130℃ for 30min. We also studied how three surfactants-hexadecyltrimethylammonium bromide, polyvinylpyrrolidone k30 （PVPk30）, and polyvinylpyrrolidone k90 （PVPk90）-affected the structure, morphology, and performance of the prepared samples, characterizing them by using X-ray diffraction, scanning electron microscopy, trans- mission electron microscopy, charge/discharge tests, and electrochemical impedance spectroscopy. All the samples prepared with or without surfactant had orthorhombic structures with the Pnmb space group. Surfactant molecules may have acted as crystal-face inhibitors to adjust the oriented growth, morphol- ogy, and particle size of LiMnPO4. The microwave effects could accelerate the reaction and nucleation rates of LiMnPO4 at a lower reaction temperature. The LiMnPO4/C sample prepared with PVPk30 exhib- ited a flaky structure coated with a carbon layer （-2 nm thick）, and it delivered a discharge capacity of 126 mAh/g with a capacity retention ratio of -99.9% after 50 cycles at 1C. Even at 5C, this sample still had a high discharge capacity of 110 mAh/g, demonstrating good rate performance and cycle performance. The improved performance of LiMnPO4 likely came from its nanoflake structure and the thin carbon layer coating its LiMnPO4 particles. Compared with the conventional polyol method, the microwave-assisted polyol method had a much lower reaction time.展开更多
基金the support from the National Natural Science Foundation of China (71673316)Beijing Food Safety Policy & Strategy Research Base, China+8 种基金the National Institutes of Health (NIH)the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) for R01 HD30880the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) for R01DK104371 and R01HL108427the NIH Fogarty Grant D43 TW009077 for financial support for the CHNS data collection and analysis files since 1989the China-Japan Friendship Hospital, Ministry of Health, for support for the CHNS 2009the Chinese National Human Genome Center at Shanghai since 2009the Beijing Municipal Centers for Disease Prevention and Control since 2011funding from the NICHD to the Carolina Population Center at the University of North Carolina at Chapel Hill (NIH GrantP2C HD050924 and T32 HD007168)。
文摘Previous studies have demonstrated that income has a significant effect on food demand in rural China. However, little research has focused on the dynamic impact of income and income distribution on food demand in rural China. Using China Health and Nutrition Survey data, this study employs a consistent two-step quadratic almost ideal demand system model, with addressed problems of endogeneity of total expenditure and zero shares, to estimate the food demand elasticities among adults in rural areas with regard to the different income strata. The results show that changes in income and income strata have significant effects on food demand in rural areas. Except for grains, all other food groups, including vegetables, oils and fats, animal products, and other foods, have positive income elasticities, and the rise in the income strata will lead to declining income elasticities for grains, vegetables, oils and fats, and animal products. Based on the estimated income elasticities, the food consumption projections indicate that reducing income inequality in rural society can improve the living standard of low-income people in terms of nutrient intakes.
基金part of“Research in the Return of Migrant Workers to Major Labor Exporting Provinces and Corresponding Allocation of Old Age Support Resources in Rural Areas”(16BSH132)a program funded by the National Social Science Fund of China(NSSFC)“Research in the Path to,and Measures for,High-Quality Rural Development Driven by Entrepreneurial Agglomeration from the Perspective of Triple Coupling”(22FH54)。
文摘The development of a multi-pillar pension insurance system is an effective solution for an aging society.Commercial pension insurance,as the third pillar of pension insurance,is an integral part of this system in China and can play a critical and complementary role in rural areas where support for the elderly is a more pressing concern and a second pillar of pension insurance remains absent.To this end,we first elaborate on the theoretical logic that commercial pension insurance can develop into one of the pillars of rural pension insurance.We then empirically test rural residents’willingness to participate in a commercial pension insurance plan(CPIP)in a probit model with household research data from rural areas in major labor-exporting provinces,such as Sichuan and Henan so as to explore whether commercial pension insurance has the potential to become one of the pillars of rural pension insurance.Our research findings can be synthesized in three points.First,rural residents out of agricultural production for five consecutive years are more willing to participate in a CPIP than other rural residents,indicating that progress in industrialization and urbanization can significantly boost such willingness.Second,the younger rural residents are more inclined to participate in a CPIP than the older generation.Third,income increases can significantly boost rural residents’willingness to participate in a CPIP.Thus,with progress in industrialization and urbanization and an increase in rural disposable income,commercial pension insurance has a promising potential in rural areas and can hopefully develop into one of the pillars of rural pension insurance.
基金financial supports from the National Natural Science Foundation of China (Grant Nos. 41571527, 41301193, 41101552,41401198)Main Direction Program (KZCX2-EW317)West Light Foundation of the Chinese Academy of Sciences (2013Yuhui)
文摘In China, farmers employed in non-farm work have become important socio-economic actors, but few studies have examined the farmers' perspective in making their work location choices. Based on "push-pull" migration theory, this paper utilizes sectional data from a 2013 survey of farmers in China's Three Gorges Reservoir area to empirically analyze the factors influencing migrant workers' choice of employment location. The results indicate that 60.46% of laborers have migrated from their home province, whereas 39.54% have remained in their home province. Focusing on personal, household, and community characteristics—in addition to the economic characteristics of the sample counties—multinomial logistic regression models reveal that farmer-laborers' employment location decisions are influenced by their personal capital endowment(age, years of education and social networks), family structure(the number of laborers, elders, children and students), home village characteristics(location, economic development level and the degree of relief of the land) and home county economic development level. Notably, male and female laborers' location decisions reveal a converging trend, and their differences are not pronounced. Per capita arable land area has little influence on location decisions, whereas the educational level of laborers has a significant impact. The results differ significantly from those found in previous studies.
基金the Beijing Food Safety Policy and Strategy Research Base at the China Agricultural University(CAU)the National Natural Science Foundation of China(NSFC)under the“Study on the Effects of Spouse Migration and Health Awareness on Rural Migrant Workers’Food Consumption,Nutrition and Health”(Grant No.71673316)the Ministry of Agriculture and Rural Affairs under the soft science research program“Study on the Bottlenecks of E-Commerce Development for Agricultural Products and Countermeasures(Grant No.2018027).
文摘Based on panel data from the Rural Fixed Point Survey of the Ministry of Agriculture over the period 2004-2016 and supplementary survey data on information and communications technology(ICT)applications in the countryside,this paper employs the difference in differences(DID)method to analyze the effects of ICT applications on rural households’agricultural total factor productivity(TFP)with mobile phone signal,internet and 3G mobile network connections as indicators,and decomposes and evaluates the constituent factors.Our findings reveal a positive effect of ICTs on rural households’TFP,which primarily stemmed from rising agricultural technical efficiency.However,ICTs exerted no significant effect on agricultural technical progress during this paper’s data period due to limited rural human capital.These findings are consistent with robustness test results based on counterfactual and matching methods.
文摘Climate extreme events have threatened food security and the second Sustainable development goals (SDGs) “zero hunger” both directly via agricultural food loss and indirectly through rising food prices. We systematically searched and used a combination of results from various models, which play a crucial role in predicting the potential impact of climate change on agricultural production and food price. Therefore, we searched online databases including EMBASE, Web of Science, Scopus, Google Scholar, and grey literature. Then observational studies were included from January 1990 to August 2021, which reported food price proportion under climate disturbances. Results showed that 22 out of 26 studies from 615 articles, identified in the meta-analysis predicted the food price ratio would be fluctuated up to 28% before 2020, while the ratio will be marked up at 31% from 2020 to 2049 and then will scale down during 2050-2100. The compiled ratio was estimated at 26% in the long period between 2000 until 2100 under climatic weather events. Drought was a significant weather disturbance with a 32% increase in food prices. Consequently, the Food price increase will significantly affect food accessibility in lower-income countries, primarily until 2050. Policymakers should prioritize and act through redesigning food security policies according to climatic extremes in their settings.
基金supported by National Key R&D Program of China(2024YFD2001100,2024YFE0214300)National Natural Science Foundation of China(No.62162008)+3 种基金Guizhou Provincial Science and Technology Projects([2024]002,CXTD[2023]027)Guizhou Province Youth Science and Technology Talent Project([2024]317)Guiyang Guian Science and Technology Talent Training Project([2024]2-15)The Talent Introduction Program of Guizhou University under Grant No.(2021)89.
文摘Segmentation of vegetation remote sensing images can minimize the interference of background,thus achieving efficient monitoring and analysis for vegetation information.The segmentation of vegetation poses a significant challenge due to the inherently complex environmental conditions.Currently,there is a growing trend of using spectral sensing combined with deep learning for field vegetation segmentation to cope with complex environ-ments.However,two major constraints remain:the high cost of equipment required for field spectral data collection;the availability of field datasets is limited and data annotation is time-consuming and labor-intensive.To address these challenges,we propose a weakly supervised approach for field vegetation segmentation by using spectral reconstruction(SR)techniques as the foundation and drawing on the theory of vegetation index(Ⅵ).Specifically,to reduce the cost of data acquisition,we propose SRCNet and SRANet based on convolution and attention structure to reconstruct multispectral images of fields,respectively.Then,borrowing from theⅥprinciple,we aggregate the reconstructed data to establish the connection of spectral bands,obtaining more salient vegetation information.Finally,we employ the adaptation strategy to segment the fused feature map using a weakly supervised method,which does not require manual labeling to obtain a field vegetation segmentation result.Our segmentation method can achieve a Mean Intersection over Union(MIoU)of 0.853 on real field datasets,which outperforms the existing methods.In addition,we have open-sourced a dataset of unmanned aerial vehicle(UAV)RGB-multispectral images,comprising 2358 pairs of samples,to improve the richness of remote sensing agricultural data.The code and data are available at egment_SR,and.
文摘This study aimed to determine the sustainability criteria of the beekeeping industry in Iran,which was performed using three-stage classical Delphi technique.The participants were 32 experts in beekeeping industry who were purposefully selected using the snowball sampling method.The criteria identified,after three Delphi stages,consisted of 70 items,which were categorized into 13 general criteria and into four economic,environmental,social,and institutional dimensions.The general criteria were presented in the form of a conceptual model,including:farmers’environmental behavior quality,beekeepers'environmental behavior quality,the quality of marketing and sales of beekeeping productions,productivity and performance improvement,amount of monetization from pollinations'right,the amount of monetization of byproducts and value added,employment rate and job stability,the level of social development of stakeholders,the quality of the role-playing of non-governmental stakeholders,the quality of extension and education new sciences and technologies to stakeholders,comprehensiveness of laws and programs,quality of role-playing of stakeholder non-governmental organizations,and the quality of the roleplaying of governmental institutions stakeholder.Using them,a comprehensive perception of the necessary criteria for the sustainability of Iran's beekeeping industry can be obtained and a comprehensive program can be designed for its implementation.
文摘We synthesized LiMnPO4/C with an ordered olivine structure by using a microwave-assisted polyol process in 2：15 （v/v） water-diethylene glycol mixed solvents at 130℃ for 30min. We also studied how three surfactants-hexadecyltrimethylammonium bromide, polyvinylpyrrolidone k30 （PVPk30）, and polyvinylpyrrolidone k90 （PVPk90）-affected the structure, morphology, and performance of the prepared samples, characterizing them by using X-ray diffraction, scanning electron microscopy, trans- mission electron microscopy, charge/discharge tests, and electrochemical impedance spectroscopy. All the samples prepared with or without surfactant had orthorhombic structures with the Pnmb space group. Surfactant molecules may have acted as crystal-face inhibitors to adjust the oriented growth, morphol- ogy, and particle size of LiMnPO4. The microwave effects could accelerate the reaction and nucleation rates of LiMnPO4 at a lower reaction temperature. The LiMnPO4/C sample prepared with PVPk30 exhib- ited a flaky structure coated with a carbon layer （-2 nm thick）, and it delivered a discharge capacity of 126 mAh/g with a capacity retention ratio of -99.9% after 50 cycles at 1C. Even at 5C, this sample still had a high discharge capacity of 110 mAh/g, demonstrating good rate performance and cycle performance. The improved performance of LiMnPO4 likely came from its nanoflake structure and the thin carbon layer coating its LiMnPO4 particles. Compared with the conventional polyol method, the microwave-assisted polyol method had a much lower reaction time.
